CROT(3)

💅 CROT (3) — the plane rotation that ate 💫

okay so bestie, welcome to the manual page for crot.f from the LAPACK library — the file lives at /home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/crot.f and this whole page is <pink>that girl</pink>. no cap. 🎀

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✨ SYNOPSIS ✨

Functions/Subroutines

• subroutine CROT (n, cx, incx, cy, incy, c, s) — CROT applies a plane rotation with real cosine and complex sine to a pair of complex vectors. 🌀

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🌸 Function/Subroutine Documentation 🌸

subroutine CROT (integer n, complex, dimension( * ) cx, integer incx,
    complex, dimension( * ) cy, integer incy, real c, complex s)

CROT applies a plane rotation with real cosine and complex sine to a pair of complex vectors. literally its whole personality. 💖

Purpose:

!>
!> CROT applies a plane rotation, where the cos (C) is real and the
!> sin (S) is complex, and the vectors CX and CY are complex.
!>

so like — C is a real one, S is doing the complex thing, and CX + CY are both complex vectors. that's the vibe check and it passed. ✨

Parameters

• N

!>          N is INTEGER
!>          The number of elements in the vectors CX and CY.
!>

the count of how many elements are chilling in CX and CY. 🍓

• CX

!>          CX is COMPLEX array, dimension (N)
!>          On input, the vector X.
!>          On output, CX is overwritten with C*X + S*Y.
!>

you come in as vector X, you leave as C*X + S*Y. glow-up fr fr. 🔥

• INCX

!>          INCX is INTEGER
!>          The increment between successive values of CX.  INCX <> 0.
!>

the step size between successive values of CX. and INCX <> 0 — zero is not it, bestie. 🙈

• CY

!>          CY is COMPLEX array, dimension (N)
!>          On input, the vector Y.
!>          On output, CY is overwritten with -CONJG(S)*X + C*Y.
!>

comes in as vector Y, leaves as -CONJG(S)*X + C*Y. note the conj and the minus, do not skip them, iykyk. 💀

• INCY

!>          INCY is INTEGER
!>          The increment between successive values of CY.  INCX <> 0.
!>

the increment between successive values of CY. and yes, the comment literally says INCX <> 0 right there in the INCY entry — not me editing, that's verbatim from the source, we don't make the rules. 😭

• C

!>          C is REAL
!>

real one. <italic>literally.</italic> 🫶

• S

!>          S is COMPLEX
!>          C and S define a rotation
!>             [  C          S  ]
!>             [ -conjg(S)   C  ]
!>          where C*C + S*CONJG(S) = 1.0.
!>

C and S tag-team to define the rotation matrix up there ☝️ and the rule is C*C + S*CONJG(S) = 1.0. that's the constraint, periodt. 👑

Author

• Univ. of Tennessee
• Univ. of California Berkeley
• Univ. of Colorado Denver
• NAG Ltd.

Definition at line 102 of file crot.f. 📍

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👑 Author 👑

Generated automatically by Doxygen for LAPACK from the source code. so no human wrote this bit, it's giving robot main character energy. 🤖✨

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and that's the whole page!! 💜 this was LAPACK, Version 3.12.0, page /home/abui.../SRC/crot.f(3) — mwah, go rotate some planes bestie, ily 🧚💖